LEPIDOSTEUS. 181 
Synopsis of the Mexican and Central-American Species *. 
I, Snout more than twice as long as the rest of the head ; no series of enlarged 
teeth on the palatinesin the adult . . . . .... OL osseus. 
II. Snout not more than once and a half as long as the rest of the head; a series of enlarged 
teeth on the palatines in the adult, as well as in the young. 
58 to 60 scales in a longitudinal series; length of head 8 to 3} in the length of 
the fish (in specimens of 8300 to500 mm.) . . . . . . . eS tristoechus. 
51 to 54 scales in a longitudinal series; length of head 32 to 3% in the length 
of the fish (in specimens of 450 to500mm.) . . 2. . . . . . . . 8. éropicus. 
1. Lepidosteus osseus. 
Esox osseus, Linn, Syst. Nat. p. 313 (1758) *. 
Lepidosteus osseus, Giinth. Cat. Fish. viii. p. 330 (1870)*; Jord. & Everm. Bull. U.S. Nat. Mus. 
xlvil. 1896, p. 109°; Meek, Publ. Columbian Mus., Zool. v. 1904, p. 5 *. 
Snout about 24 times as long as the rest of the head. Dorsal 7-8. Anal 8-9. 58 to 62 scales in a 
longitudinal series, 
Hab. United States from the Great Lakes to the Rio Grande?2; North-eastern 
Mexico ¢. 
In Mexico recorded by Meek from San Juan in Nuevo Leon, Forlon in Tamaulipas, 
and Valles in San Luis Potosi. 
Total length 1500 mm. 
2. Lepidosteus tristoechus. 
Esox tristoechus, Schneid. Bloch’s Syst. Ichth. p. 895 (1801)’. 
Lepidosteus viridis (non Gmelin), Giinth. Cat. Fish. viii. p. 829 (1870) *. 
* The three species here recognised comprise the subgenera Lepidosteus (L, osseus) and Aiéractosteus 
(L. tristoechus and L. tropicus). There is a third subgenus, Cylindrosteus, with the dentition of Lepidosteus, 
but with the snout shorter and broader than in ZL. osseus, only a little longer than the rest of the head. This 
subgenus is usually considered to include a single species, L. platystomus, Rafin., which is said to range from 
the Great Lakes to Texas. Examination of the specimens in the British Museum leaves no doubt that 3 or 4 
distinct species belong to this section ; some of these may extend into North-eastern Mexico. 
L. productus, Cope, seems to be different from L. platystomus or any of the species which I have seen. 
Specimens of L. platystomus from Illinois and Louisiana have 60 to 62 scales in a longitudinal series and the 
width of the snout, at the level of the angles of the mouth, not more than } the length of the upper jaw. A 
fish from St. Louis, received from the Museum of Comparative Zoology, closely resembles L. platystomus, and 
may not be specifically distinct, but has larger scales (55 or 56 in a longitudinal series) and corresponds in 
every way to L. agassizit, Dum., also described from a St. Louis specimen from the Museum of Comparative 
Zoology. The type of Z. grayi, Agass. (600 mm, long), and a much larger specimen, also from Louisiana, 
differ from L. platystomus in having a much broader snout (width at the angles of the mouth 2} in the length 
of the upper jaw). Z. zadocki, Dum., is evidently the same as LZ. gray. 
